The objective of this project is the development, field testing, and evaluation of a screening procedure to aid in early identification of children with social and emotional dysfunction. For the years 1976-1979, the objectives have been: 1) to develop and implement a comprehensive screening program for preschool children; 2) to assess social and behavioral outcomes for 700 of these children one year later; 3) to complete criterion validation and clinical comparison studies; and 4) to construct a comprehensive model of social and emotional risk based on the screening and criterion measures. For 1979-1982 we propose to : 1) determine the sensitivity and specificity of the screening model over time by following the 1977 cohort of 700 childern annually with appropriate criterion measures; 2) follow two subsamples of children with intensive study by clinical observation and interview to identify characteristics, environments, and life events contributing to a child moving into risk status. The project offers a significant opportunity to examine research issues bearing directly on policy decisions: 1) optimal timing of screening procedures; and 2) the even more crucial question of whether large screening programs should continue to be promoted. The longitudinal thrust of the proposal (1976-1979 and 1979-1982) will allow for a thorough evaluation of the efficiency of preschool screening and its implication for programming and policy.